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Dewalt battery question

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#22 ·
Tmrrptr said:
Sry to inject a negative, but I just don't feel Ryobi makes professional quality tools. They are cheaper for a reason.

I can not believe anyone would select them over Dewalt ! for any reason.
r
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Ryobi does make a cheaper tool...They are however VERY good for the price. When you are paying 5x more for a dewalt/makita/bosch, etc etc...Those tools better be better.

On the plus side to Ryobi is that you can buy a battery for around $20.

Another new plus side to the Ryobi is there new Li tools that came out. You can use that battery in all the older 1+ tools and vice versa.

I personally wouldn't use the older ryobi 1+ tools because I use them too much, but for the average DIYer they a great buy. Although I am fairly impressed w/Ryobi's new Li line...seem to be very solid, though I have only used them slightly.
 
#26 ·
DEWALT NANOs

Hey All,
Just a little more fyi on the Dewalt Nano, My brother-in-law works for B&D in Maryland and he is highly impressed with these tools and everyone is right, they should be hitting the market in late Oct, early Nov.:no: Good for everyone here but bad for me, I have a business rebuilding the Nicad packs and these will probably hurt my business, since I just started this in January it's my luck that the companies come out with these tools now...Why couldn't they wait until i made enough money on my business to get out of debt!!!!!!!!! Just kidding, these new cells are destined to become the hot lick in the industry I suppose.
Greg
 
#27 ·
Powerworldhk said:
Please kindly go to xxxxxxxxxxxxxx to see all kinds of power tool batteries like dewalt batteries, makita batteries, Bosch batteries... ,high quality and cheap price directly from China!:clap:
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Powerworldhk said:
Go to xxxxxxxxxxxxxx you can find even lower price for dewalt batteries and universal chargers:thumbup:
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WTF dude?
You join today and immediately start selling your wares - not once but twice and in the same thread - w/o so much as an introduction?

I have a suggestion as to where you should go :censored:

I suggest an immediate ban.
Can I get an "AMEN"?
 
#28 ·
AMEN brother, AMEN.
 
#31 ·
I know this thread is older but thought i would share that home depot, lowes, and amazon.com all have a 2 pack dewalt 18 volt xrp battery packs for 119.00 dollars. It's a pretty good deal considering the rebuild site mentioned in here charges 45.00 per battery plus shipping to them, so around 100.00 for rebuilt batteries or 119.00 for brand new and you can pick them up locally.
 
#33 · (Edited)
GSW327 said:
... One thing to do to a battery that won't hold a charge is try to hit it with high amperage to burn off the so called wiskers that begin to grow between the plates in the cells as they are recharged. This can be accomplished by connecting 2 -18v packs together (positive to negative on the packs leaving 1 positive and one negative pole open, this can be accoplished by using aligator clamps as leads) this will create a 36v pack with approximatly 9 amps of DC power, then momentarily touch the positive and negative terminals with leads from the two packs, several times, then test the voltage in the bad pack. ...
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Hello, I have a 12v Ryobi drill, as well as an 18v Ryobi drill. Both 18v batteries work well (as does their drill), and the 12v drill works well, but the 12v batteries only last a very short time. I charged them, then a couple days later I tried them and already the drill was barely turning.

I read about putting two 18v battery packs together then shocking the 12v battery packs with the combined packs. Another thread mentioned to be careful of polarity.
I see you say hook up positive & negative between the two batteries, but you don't mention which way to hook up to the 12v.

All the batteries have polarity markers on the plastic near the metal contacts, so do I hook up positive to positive or positive to negative? In other words, in the following picture, do I hook it up using the brown or the blue lines?
Also, do I only need one of the 18v batteries, or should I use both?
 

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#34 · (Edited)
Don't discharge them completely. 12v packs are built of 10 1.2v cells and ideally they're all exactly the same capacity; however they're not in reality. There is the weakest cell somewhere that will drop out first and when you continue using it, that cell basically gets charged backward by the remaining batteries. This puts a lot of stress on that cell and when it dies, the whole pack is basically done since you can't just change a cell.

Charge them when you start noticing loss of power.


Ck.asdf said:
Hello, I have a 12v Ryobi drill, as well as an 18v Ryobi drill. Both 18v batteries work well (as does their drill), and the 12v drill works well, but the 12v batteries only last a very short time. I charged them, then a couple days later I tried them and already the drill was barely turning.
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You've got a dead cell that's losing charge. Once there's one dead cell in series, it acts as a bottle neck. Might as well give the drill + charger away or sell it to someone who's got a fleet of batteries and buy a new kit.

Battery packs and chargers are expensive. Two batteries + a charger usually costs the same or more than a whole new kit.
The two packs that came with my Makita died. After seeing how expensive the replacements are, I just dumped mine on eBay and got a whole new kit.
 
#35 ·
Teetorbilt said:
Ask anybody that's into R/C racing, they build their own battery packs. It's not that big of a deal, the kid a few doors down used to do mine, unfortunately he now has a car and has discovered girls. :cry:

Opening the packs can be a bigger challenge than replacing the cells, on lower priced tools the cases are sonicly welded and hard to access.

You can find the cells at hobby shops.
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girls and cars are kooler than batteries...arent they?:tongue_smilie:
 
#36 ·
Last year I scored 3 DeWalt 12 V kits w/2 batteries for 79 bucks each a Blowes, last week I got the same kits at 99 bucks each. With battery replacements at 65 dollars each, it's a no brainer. These are nice drills too, 1/2" chucks with 3 speed gearbox.:thumbup:
 
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#37 ·
Electric_Light said:
Don't discharge them completely. 12v packs are built of 10 1.2v cells and ideally they're all exactly the same capacity; however they're not in reality. There is the weakest cell somewhere that will drop out first and when you continue using it, that cell basically gets charged backward by the remaining batteries. This puts a lot of stress on that cell and when it dies, the whole pack is basically done since you can't just change a cell.

Charge them when you start noticing loss of power.



You've got a dead cell that's losing charge. Once there's one dead cell in series, it acts as a bottle neck. Might as well give the drill + charger away or sell it to someone who's got a fleet of batteries and buy a new kit.

Battery packs and chargers are expensive. Two batteries + a charger usually costs the same or more than a whole new kit.
The two packs that came with my Makita died. After seeing how expensive the replacements are, I just dumped mine on eBay and got a whole new kit.
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There's a few rules with every type of cell.

NI-CAD - Always fully discharge till tool stops running as they have very bad memory affects.
NI-MH - Never fully discharge as cells can reverse polarity and if you leave for any length of time charge them to 75% and leave in a cool place.
LI-ION - Again never fully discharge. If you start to have didgital memory effects then a full discharge once every 30-50 times wont hurt the cells. Again if you need to leave for any length of time keep them cool and at 75% charge rate.

If you look after you cells and keep them out of the sun and dont drop them then any of the above cells should last 2-3 years of good use.
 
#38 ·
BCConstruction said:
There's a few rules with every type of cell.

NI-CAD - Always fully discharge till tool stops running as they have very bad memory affects.
NI-MH - Never fully discharge as cells can reverse polarity and if you leave for any length of time charge them to 75% and leave in a cool place.
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They both suffer from polarity reversal, because the pack is always made of multiple cells that are less than perfectly matched. The weakest cell gets reversed first, period. Reversal is harmful to both NiCd and NiMH.

When you stop using the pack when the tool starts showing a sign of slowing, it is pretty much fully discharged. Memory effect isn't a big deal unless you're frequently using it for a little bit, then charge it during break just to top it off.


LI-ION - Again never fully discharge. If you start to have didgital memory effects then a full discharge once every 30-50 times wont hurt the cells. Again if you need to leave for any length of time keep them cool and at 75% charge rate.

If you look after you cells and keep them out of the sun and dont drop them then any of the above cells should last 2-3 years of good use.
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No such thing as "digital memory effect". They're supposed to be stored at about 40% charge. Storing them fully charged will diminish reusable capacity significantly. At least, with the traditional Li-Ion chemistry. The new phosphate chemistry that's in use, I'm not too sure about.
 
#39 ·
Electric_Light said:
They both suffer from polarity reversal, because the pack is always made of multiple cells that are less than perfectly matched. The weakest cell gets reversed first, period. Reversal is harmful to both NiCd and NiMH.

When you stop using the pack when the tool starts showing a sign of slowing, it is pretty much fully discharged. Memory effect isn't a big deal unless you're frequently using it for a little bit, then charge it during break just to top it off.




No such thing as "digital memory effect". They're supposed to be stored at about 40% charge. Storing them fully charged will diminish reusable capacity significantly. At least, with the traditional Li-Ion chemistry. The new phosphate chemistry that's in use, I'm not too sure about.
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The thing with ni-cad chargers is they are nomally a very basic charger and will force the cell to charge even if reveresed or faulty. This aint so simple with Ni-MH as they use either peak detection or temp detection or combination of both. NI-MH cell can false peak very often if discharged to much and they the cells that reverse polarity can get to hot and also false detect the charge. Didgital mem is a big problem with laptop batts where you always keep them in the laptop but never disconnect to batterey. The sensors that test the batt can give you flase infomation about the batt being bad but infact the batterey is fully charged. This can nomaly be solved with a discharge but not always. Wont very often happen in poer tools as they are drained ofetn but it does happen. Do a google search for each type of batt as it will give you full details about the good and bad point of each. Im not keen on LI-ION for some things as i have had them exploded 1 to many times but my power tool batts so far have been good.
 
#40 ·
BCConstruction said:
The thing with ni-cad chargers is they are nomally a very basic charger and will force the cell to charge even if reveresed or faulty.
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A polarity reversal won't instantly kill the cell, but since the weak cell will be the one getting reversed each time, it will fail sooner than necessary by letting the tool run until it stops running.

This aint so simple with Ni-MH as they use either peak detection or temp detection or combination of both. NI-MH cell can false peak very often if discharged to much and they the cells that reverse polarity can get to hot and also false detect the charge.
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The basic charging mechanism is the same for NiCd and NiMH. The termination is based on voltage, temperature, or a combination of both. An old Makita NiCd charger was purely temperature controlled.

The charger forced curren into the battery pack until the thermostat within the pack tripped (which is what the third contact connects to)

Many newer charger employs a less brute force method and can actually charge both NiMH and NiCd packs. NiMHs are just not as tolerant to abuse.

Didgital mem is a big problem with laptop batts where you always keep them in the laptop but never disconnect to batterey. The sensors that test the batt can give you flase infomation about the batt being bad but infact the batterey is fully charged.
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Laptops use SMBus to manage battery pack and measures the amount of charge going into and going out of battery to estimate the remaining capacity, but the prediction shifts from actual capacity, so it needs "calibration". This is different from "memory". Power tools and even most cell phone batteries don't actually track the power leaving and entering the battery. It measure the voltage and gives you a 3 or 4 bar indicator that gives a very rough estimate of remaining power. This is why it's common to see a phone drop to 2 bar of battery while talking, then jumps back to 3 bar after you're off the phone.
 
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